Nozzle angle

This equation, rewritten in terms of the absolute veloeity and the nozzle angle a for maximum utilization, ean be shown as... 

In most designs, the reaetion of the turbine varies from hub to shroud. The impulse turbine is a reaetion turbine with a reaetion of zero (R = 0). The utilization factor for a fixed nozzle angle will increase as the reaction approaches 100%. For = 1, the utilization factor does not reach unity but reaches some maximum finite value. The 100% reaction turbine is not practical because of the high rotor speed necessary for a good utilization factor. For reaction less than zero, the rotor has a diffusing action. Diffusing action in the rotor is undesirable, since it leads to flow losses. 

To see if this drum size can be significandy reduced using the approach proposed in this article, some additional information is needed and the following is assumed inlet nozzle angle 0,=3O deg. inlet nozzle dia. vapor-droplet velocity ( , 56.6 ft/s hence. t/ = L cos 0,=49 ft/s, and Lp— stn 0,=28.6 ft/s. (The parameters 0( and dn can. of course, be adjusted. The effects of varying these parameters will be discussed.)... 

Mixer material SU-8 resist Nozzle angle (relative to array front) 28°... 

For example, if the nozzle angle is 20°, the inlet and outlet blade angles will each be 36°, and the optimum speed ratio will be 0.47, giving a blade efficiency of 0.883. 

Figure 1S.S Blade efficiency for an operating impulee blade with nozzle angle = 20°.

We may find the maximum blade efficiency for a given nozzle angle, ai, by differentiating with respect to speed ratio, Rb, and setting the result to zero. (We will assume that the nozzle efficiency over the moving blades is unaffected by changes in speed ratio, Rb-) This yields the optimal speed ratio as... 

Akiyama T, Marui T. Dust collection efficiency of a straight-through cyclone effects of duct length, guide vanes and nozzle angle for secondary rotational flow. Powder Technol 58 181, 1989. 

To make the analog computation with parameters of fixed position of oxygen lance (1.6 m from the bottom), oxygen pressure at the entrance of the oxygen lance was fixed at 0.9 Mpa and different oxygen lance nozzle angles were fixed as 15 16 ° and 17 °. Therefore, the simulated... 

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